Thursday, October 17, 2019

Independent study Essay Example | Topics and Well Written Essays - 3000 words

Independent study - Essay Example he individual reaches the medical care system, the incidence of sudden death and deaths that occur before these individuals could receive medical supervision constitutes the major challenge to the present system of cardiovascular care. (Harken, 2004; Wenger, 2004) In the United Kingdom alone, roughly 20 million local citizens survive from heart attacks and stroke each year who requires a continuous clinical care. (WHO, 2007) Considering that those individuals who have had heart attacks and strokes are at high risk of repeated attacks including death, it is essential for health care and clinical nurses particularly those who are working in a cardiology ward to learn more about the importance of proper administration of oxygen therapy immediately after a myocarial infarction attack. Aiming to enable the readers understand more about the topic, the researcher will discuss about the rationale for choosing the topic particularly the relevance of administering oxygen therapy with myocardial infarction as well as with working in a cardiology ward. Eventually, a literature review will be conducted focusing on the general information about myocardial infarction including the major causes of myocardial infarction; the negative impact of having myocardial infarction; the importance of early intervention on myocardial infarction attack; as well as the impact of oxygen therapy administration to patients with myocardial infarction. Based on the gathered literature study, the strengths and limitations of the current practice including some recommendations for the practice development will be thoroughly discussed. According to Dr. Richard Lippman, a renowned researcher, â€Å"oxygen deprivation is the major cause of heart attacks among 1.5 million people each year.† (OxyGenesis Institute, 2007) Oxygen, one of the most important elements and nutrients of all life, is delivered to the human cells by the blood. Considering that the coronary arteries or blood vessels of individuals

Wednesday, October 16, 2019

Literature review on ethical issue between employees and their Essay

Literature review on ethical issue between employees and their manegars - Essay Example The daily interaction, collaboration and interpersonal relationships required from managers and employees create tensions and issues that are considered normally pervading the working environment. Apart from operational concerns, managers and employees are faced with contrasting beliefs, values and preferences that occur because of the diversity in personalities, traits, cultural orientations and demographical factors that form each individual in the organization. These beliefs fall under ethical issues in business, defined as â€Å"â€Å"the principles and standards that guide behavior in the world of business† (Ferrell, Fraedrich & Ferrell, 2009, 6). In this regard, the current study aims to proffer a review of related literature on the subject of ethical issues between managers and employees. The theoretical framework and impetus for the review came as a result of an interview with a legal researcher for the Saudi – Central Bank, who identified problems which are et hical in nature and existed in their organization, currently affecting job satisfaction and productivity of employees. Ethical Issues in Business Organizations Ethical behavior have been identified to manifest actions that are â€Å"morally accepted as "good" and "right" as opposed to "bad" or "wrong" in a particular setting† (Sims, 1992, 506). ... According to Martires and Fule (2004), the culture of an organization influences the ethical climate that pervades. Organizational culture is a set of symbols, myths, ceremonies that reflect the underlying values and beliefs of the organization or its work force. This statement is supported by Hunt (1991) and Schneider and Rentsch (1991) who emphasized that there are factors that influence diversity in ethical climates of organizations, to wit: â€Å"personal self-interest, company profit, operating efficiency, individual friendships, team interests, social responsibility, personal morality, rules and standard procedures, and laws and professional codes† (cited in Sims, 1992, 510). As such, more detailed ethical issues facing human resources in organizations, particularly between managers and employees, are revealed by CiteHR (n.d.) to wit: (1) â€Å"discrimination issues include discrimination on the bases of age (ageism), gender, race, religion, disabilities, weight and att ractiveness; (2) issues surrounding the representation of employees and the democratization of the workplace: union busting, strike breaking; (3) issues affecting the privacy of the employee: workplace surveillance, drug testing; (4) issues affecting the privacy of the employer: whistle-blowing; (5) issues relating to the fairness of the employment contract and the balance of power between employer and employee: slavery, indentured servitude, employment law; and (6) occupational safety and health† (CiteHR, n.d., par. 1). In the case of the legal researcher for the Saudi – Central Bank, the ethical issue that existed between managers and employees was manifested in the way the manager discriminated against underperforming employees which further

Tuesday, October 15, 2019

Macroeconomics Discussion Essay Example | Topics and Well Written Essays - 750 words

Macroeconomics Discussion - Essay Example Money supply is the money circulating in the economy which is created by the FED, the depositors, and investors. Each of the 12 Federal Reserve banks perform the following: a. clear checks; b. issue new currency; c. withdraw damaged currency from circulation; d. administer and make discount loans to banks in their districts; e. evaluate proposed mergers and applications for banks to expand their activities; f. act as intermediaries between the business community and the Fed; g. examine bank holding companies and state-chartered banks; h. collect data on local business conditions; i. use their staff of professional economist to research topics related to monetary policy (Mishkin 369- 370). The money supply can be changed by increasing our deposits held by banks. This money creates a repercussion of effects in the economy when borrowed by companies who use this for their operations. Through the money multiplier, the invested money could increase employment an output more than its actual value. (3.) You are appointed as the chair of FRB. Congratulations! Chair, economy is in recession what are the policy measures you will undertake to push GDP toward potential GDP What are the problems of implementing monetary policy in practice Under an expansionary policy, the central bank must increase the money supply and lower the short- term interest rates. The Fed can engage in the following: a. open market purchase which expands reserves and monetary base; b. lower the discount rate which encourages borrowing by banks; or c. lower the reserve requirements among banks. Part Three: write a few sentences summarizing what you have learned and how learning this will help you personally. :) Thanks!! The most important thing which I have learned so far is the interdependence of the players in an economy. It is very important to note that the action of one player can have a tremendous effect in other sectors. Learning the functions of money, how money is controlled and managed, and how it can be used to stimulate or slow down the economy is really something very interesting to me. Knowing that my actions can influence the economy, I can now align my decisions in order to help the FED to achieve its economic goals. This is very important noting the forecasted downturn in the US economy in the coming future. Part Four:What is money supply, M1 and M2 which definition of money supply is more liquid and why M1 is the narrowest measure of money which includes currency, checking account deposits and travelers checks. The M2 includes the M1 plus other assets that have check-writing features such as small-denomination time deposits,

Monday, October 14, 2019

Control system for microgrid

Control system for microgrid Abstract In this study an example of a microgrid composed of diesel generator and two uninterruptable power supply systems is considered. This microgrid installed in the three buildings of the Tallinn University of Technology. This paper deals with how to implement a distributed control and monitoring system based on the Ethernet network in the microgrid. The paper describes a control strategy to implement both grid connected and islanded operation modes of the microgrid. Keywords Control system, diesel generator, microgrid Introduction Distributed generation (DG) is becoming an increasingly attractive approach to reduce greenhouse gas emissions, to improve power system efficiency and reliability, and to relieve todays stress on power transmission and distribution infrastructure [1]. Distributed generation encompasses a wide range of prime mover technologies, such as internal combustion engines, gas turbines, microturbines, photovoltaic, fuel cells and windpower [32]. A better way to realize the emerging potential of DG is to take a system approach which views generation and associated loads as a microgrid [21]. Microgrid is a concept of defining the operation of distributed generation, in which different microsources operate as s single controllable system that provides power and heat to a cluster of loads in the local area [3], [8] [9]. A well designed microgrid should appear as an independent power system meeting the power quality and reliability requirements [3]. The primary goal of microgrid architectures is to significantly improve energy production and delivery to load customers, while facilitating a more stable electrical infrastructure with a measurable reduction in environmental emissions [10]. The most positive features of microgrids are the relatively short distances between generation and loads and low generation and distribution voltage level. The main function of a microgrid is to ensure stable operation during faults and various network disturbances. The microgrid is a promising concept in several fronts because it [18]: provides means to modernize todays power grids by making it more reliable, secure, efficient, and de-centralized; provides systematic approaches to utilize diverse and distributed energy sources for distributed generation; provides uninterruptible power supply functions; minimizes emissions and system losses. Despite many advantages of microgrid there remain many technical challenges and difficulties in this new power industry area. One of them is the design, acceptance, and availability of low-cost technologies for installing and using microgrids [4]. The increased deployment of power electronic devices in alternative energy sources within microgrids requires effective monitoring and control systems for safe and stable operation while achieving optimal utilization of different energy sources [35]. Microgeneration suffers from lack of experience, regulations and norms. Because of specific characteristics of microgrids, such as high implication of control components, large number of microsources with power electronic interfaces remains many difficulties in controlling of microgrids. Realization of complicated controlling processes in microgrids requires specific communication infrastructure and protocols. During the process of microgrid organization many questions concerning the protection and safety aspects emerge. Also, it is required to organize free access to the network and efficient allocation of network costs. The predominant existing distributed generation is based on an internal combustion engine driving an electric generator [36]. To investigate various aspects of integration of alternative energy sources such as conventional engine generators, this paper proposes a prototype of the microgrid for three academic buildings at the Tallinn University of Technology which consists of a diesel generator, and batteries storage with power electronic interface. The main goal of this work is to design an intelligent control system of the microgrid that is efficient enough to manage itself for power balance by making use of state of the art communication technology. Moreover, the aim of this paper is to describe the control strategy of the microgrid operation in both stagy state modes. This control system enables the microgrid system to balance the electric power demand and supply and to simultaneously control the state of power network. Microgrid Theoretical Background A microgrid is described as a small (several MW or less in scale) power system with three primary components: distributed generators with optional storage capacity, autonomous load centers, and system capability to operate interconnected with or islanded from the larger utility electrical grid [10], [11]-[13]. According to [39], [22], multiple facility microgrids span multiple buildings or structures, with loads typically ranging between 2MW and 5MW. Examples include campuses (medical, academic, municipal, etc), military bases, industrial and commercial complexes, and building residential developments. Microgrids include several basic components for operation [3], [4]. An example of a microgrid with is illustrated in Fig.1. Distributed Generation Distributed generation units [1] are small sources of energy located at or near the point of use. There are two basic classes of microsources; one is a DC source (fuel cells, photovoltaic cells, etc.), the other is a high frequency AC source (microturbines, reciprocating engine generators, wind generators), which needs to be rectified. An AC microgrid can be a single-phase or a three-phase system. It can be connected to low voltage or medium voltage power distribution networks. Storage Devices Distributed storage technologies are used in microgrid applications where the generation and loads of the microgrid cannot be exactly matched. Distributed storage provides a bridge in meeting the power and energy requirements of the microgrid. Distributed storage enhances microgrid systems overall performance in three ways. First, it stabilizes and permits DG units to run at a constant and stable output, despite load fluctuations. Second, it provides the ride through capability when there are dynamic variations of primary energy (such as those of sun, wind, and hydropower sources). Third, it permits DG to seamlessly operate as a dispatchable unit. Moreover, energy storage can benefit power systems by damping peak surges in electricity demand, countering momentary power disturbances, providing outage ridethrough while backup generators respond, and reserving energy for future demand. There are several forms of energy storage, such as the batteries, supercapacitors, and flywheels. Interconnection Switch The interconnection switch is the point of connection between the microgrid and the rest of the distribution system. New technologies in this area consolidate the various power and switching functions (power switching, protective relaying, metering, and communications) traditionally provided by relays, hardware, and other components at the utility interface into a single system with a digital signal processor. The interconnection switches are designed to meet grid interconnection standards. Control System The control system of a microgrid is designed to safely operate the system in grid-parallel and stand-alone modes. This system may be based on a central controller or imbedded as autonomous parts of each distributed generator. When the utility is disconnected, the control system must control the local voltage and frequency, provide (or absorb) the instantaneous real power difference between generation and loads, provide the difference between generated reactive power and the actual reactive power consumed by the load, and protect the internal microgrid. Structure of the Proposed Microgrid The microgrid installed in three buildings of the Tallinn University of Technology (TUT): Faculty of Power Engineering, TUT Library, School of Economics and Business Administration. Consequently, according to the classification given in [22], this power system can be defined as a multiple facility microgrid. Fig.2 illustrates the various components of the power system of the microgrid at TUT. The structure of the microgtid for the campuses of the TUT is proposed. Fig.3 shows a schematic of the power system. Microgrid systems targeted in this study are autonomous areas having the power demand of several kilowatts including a diesel generator, two uninterruptable power supply (UPS) systems with batteries storage, and loads. They are connected to the power electronic interface forming local AC network with 230V, 50Hz. The diesel generator is used as the main distributed energy resource in this microgrid. It has a nominal power of 176kW/220kVA, voltage of 240V/400V and maximum current of 318A. This generator is connected to the AC bus via the automatic relay logic (ARL2). The ARL2 is continuously observing it both sides: the main grid and the microgrid. If there is a fault in the general grid, the ARL2 will disconnect the microgrid, creating an energetic island. The battery banks (E1 and E2) are used as the distributed energy storage devices in the microgrid to insure continuous supply of the local load. They are interfaced to the electrical network through the two UPS systems: UPS1 (160kVA), and UPS2 (240kVA). Hence, we can conclude that the microgrid has two main possible operation modes: grid-connected and islanded mode. Main customers of the microgrid are the computers and servers located in the laboratories and office rooms in the three buildings of TUT. The clients in the Library Building (computers) are interfaced to the electrical network using ARL1. In addition, four experimental loads (Experimental loads 1..4) are used that can be connected to the distributed shield located in the Laboratory of Electrical Drives. The nine intelligent sensors (P1..P9) assign these loads. Their task is to measure electrical power and energy parameters of the network, such as voltage, current, power, energy, power factor and transmit this information to the controller. The microgrid is connected to the general city electricity grid using two two-section transformer substations (6000kV/400kV) located in the Faculty of Power Engineering and the School of Economics and Business Administration Buildings. Description of the Control System Taking into account the configuration and features of the power network of the Tallinn University of Technology, the control system structure for the microgrid is designed with the following specifications: the balance of electric power demand and supply of power network are provided; both the steady state modes and the transient performance of the microgrid are achieved. A block diagram of the hierarchical control system which is based on the multiagent technology [40], [41], is demonstrated in Fig.4. The design of the control system can be divided into hardware and software. The control structure of the microgrid has three levels: Operator console and application server; Central controller (CC); Local controllers (LC) and measuring devices. Operator console is a computerized workstation with special software which comprises of supply and demand calculation units, monitoring units, control schemes and dispatching units. The function block diagram of the software is shown in Fig.5. The operator console heads the hierarchical control system. Its main goals of are: to keep track of the whole system by monitoring the status of the communication nodes and generating units; to collect data from the measuring devices; to calculate supply and demand of power; to visualize information received; to display the basic modes of the microgrid; and to transfer control commands to the central controller. Application server is designed for archiving data received from the measuring devices. The main interface between the operator console and others communication nodes of the microgrid control system is the central controller. It is the main responsible for the management of the microgrid. for the optimization of the microgrid operation. The central controller operates in real time. Its main functions are: connection and disconnection of the microgrid, the synchronization process, the detachment of loads. In addition, the aims of the central controller are: to collect information from the measuring devices; to transfer data from the operator console and the application server; to manage the power supply switches; and to transmit the control commands to the local controllers. Group of the local controllers are related to the third hierarchical control level. They include microsource controller that located in the distributed resources of the microgrid. It manages active and reactive power production levels at the diesel generator. Moreover, the microsource controller is responsible for the maintaining desired steady-state and dynamic performance of the power network. The other local controllers are located in the two UPS systems. Their main goals are to provide management of charge of the batteries storage. Measuring process Information required by the proposed monitoring and control system is voltage, current, power, energy, and power factor measurements. Real-time information is acquired through the intelligent measuring devices located at the output of the energy source, at the input of each loads, and at the both UPS systems. In this system, Allen-Bradley Powermonitor 3000 [25] is used to measure these instantaneous values. It implements real-time power monitoring with 50 ms selectable update rate. Such operating information is displayed in real-time for monitoring and energy management purposes. Communication network A communication infrastructure is needed between the central controller and the local controllers [23]. The short geographical span of the microgrid may aid establishing a communication infrastructure using low-cost communications. The adoption of standard protocols and open technologies allows designing and developing modular solutions using off-the-shelf, low-cost, widely available, and fully supported hardware and software components. At the present time, many low cost microcontrollers include at least an Ethernet controller, standalone cheap controllers are also available. The main advantages of using Ethernet are: the transition from a centralized control to a distributed control; wiring reduction no need for point to point connections. This solution provides flexibility and scalability for low-cost implementations. Taking these into account, the Ethernet industrial protocol has been chosen in this microgrid as communication network for data transfer for all those control units. The amount of data to be exchanged between network controllers includes mainly messages containing set-points to LC, information requests sent by the MGCC to LC about active and reactive powers, and voltage levels and messages to control microgrid switches. The LC is responsible of collecting local information from the attached energy resource and takes some real-time decisions based on the control algorithm. The communication network of the control system is illustrated in Fig.6. Every communication node has to get registered to the master server. The node sends its information to the master server through diverse communication channel. Furthermore, this topology provides an opportunity for immediate control center access via remote consoles and web based laptops for necessary actions to be taken. To include new generation resources or storage devices in a flexible manner into the microgrid, multi-agent technologies [40] might be applied. The proposed hierarchical control scheme provides a flexible platform to make high level decisions. Control Strategy of Operation of the Microgrid A microgrid may operate either connected to the main grid or disconnected from it. There are two steady states of operation, grid-connected (Mode-G) and islanded (Mode-I). Furthermore, there are two transient modes of operation, transfer from Mode-G to Mode-I and transfer from Mode-I to Mode-G. The key issue of the control is how to maintain the voltage and frequency stability of the microgrid [20]. Grid-connected mode In the grid-connected operation mode, the main function of a DG unit is to control the output real and reactive power. The real and reactive power generated by a DG can be controlled through current or voltage regulation, thus the DG output power control schemes can be generally categorized as current-based and voltage-based power flow control [43]. During Mode-G operation, the voltage and frequency of the microgrid is set by the main grid. The aim of the uninterruptible power supply systems is to obtain energy backup as much as possible, so during Mode-G operation, the main grid, the microgrid or both of them, will charge the batteries [20]. In grid-connected mode the balance between the generation and the consumption as well as the control of the parameters of the system is guaranteed by the utility grid. Thus, generators are regulated with the criterion of optimized economic exploitation of the installation [23]. Concerning the programmable generator, the objective of the control is to optimize the microgrid performance. Islanded mode The MG operates autonomously, in a similar way to physical islands, when the disconnection from the main grid occurs [37]. When the grid is not present, the ARL2 disconnects the microgrid from the grid, starting the autonomous operation. The instant at which the intentional islanding occurs must be detected in order to the inverter changes between grid-connected to intentional island modes. The detection is achieved using an algorithm described in [23]. When the main distribution network is faulted, the fault current will flow into the main grid from the microgrid continuously. At the same time, the circuit breaker of microgrid should detect the frequency and voltage-drop, and open in time, which makes the microgrid disconnect automatically from the main grid and change to islanded operation mode. Diesel generator should adopt the reasonable control strategies to ensure the stability of frequency and voltage in microgrid [42]. While switched from Mode-G to Mode-I, the UPS system operates in voltage control mode, is setting the voltage and frequency of the microgrid through absorbing or releasing energy. In islanded mode, due to the unavailability of the utility grid, two requirements must be fulfilled: the power balance between the generation and the consumption and the control of the main parameters of the installation (voltage amplitude and frequency). In synchronous islanded mode this reference is the same as the grid voltage. This mode is also called synchronization mode and it is the mode that necessarily precedes a reconnection with the grid. The control system is responsible for assuring the power balance. In case of energy excess the management system can limit the output power of the diesel generators power in order to avoid the operation in extremely inefficient low power generation modes. On the contrary, if all the available power is not enough to feed the local loads, the management system will detach non-critical loads. The control system is voltage controlled and it regulates the main parameters of the system. The UPS systems sets the voltage and frequency of the islanded microgrid and maintains them within acceptable limits by injecting or absorbing active power and reactive power as required. As soon as the presence of mains is detected, the microgrid control system uses feedback information from the mains voltage to adjust the energy storage unit voltage and frequency control loops to synchronize the microgrid voltage with the main voltage of the main grid. Transition from Grid-Connected to Islanded Mode There are various islanding detection methods proposed for DG systems [44]. As mentioned above, there is a different control strategy when the laboratory-scale microgrid system operates in Mode-G or Mode-I. If there is a transition between these two modes, the control mode of the battery inverter will change. A switching circuit, as shown in Fig.7, is designed to realize this transition [20]. A load-voltage control strategy proposed by [23] is employed to provide the operation of the microgrid. Disconnection of the microgrid from the grid can be provoked by many causes, like unsatisfactory grid voltage (in terms of amplitude or waveform) or even economic aspects related to power price. In order to monitor grid voltage characteristics a Voltage monitoring module is required. This module measures continuously the rms grid voltage comparing it with a preestablished threshold value. When any of the phase voltages goes down the threshold value (0.9 pu in this case) the detection signal is activated. If 20 ms after the first detection this signal is still activated the microgrid must be disconnected from the utility grid and it must pass to islanded operation mode, otherwise the microgrid will remain connected to the utility grid. This way unnecessary islandings are avoided and selectivity is respected. A 20 ms time window has been chosen after verifying through experimental tests and standards [47] that a personal computer (which is considered as the most critical residential lo ad in this microgrid) is not affected by a 20 ms voltage interruption. As soon as the microgrid is disconnected from the grid, the programmable generator controller passes from a power control mode to a voltage control mode. Microgrid power consumption is also continuously measured in order to detach non-critical loads if there is no enough local available power. In addition if consumption or generation conditions are modified and it becomes possible to feed all the local loads, non-critical loads will be reconnected. Transition from Islanded to Grid-Connected Mode When the grid-disconnection cause disappears, the transition from islanded to grid-connected mode can be started. To avoid hard transients in the reconnection, the diesel generator has to be synchronized with the grid voltage [23]. The DG is operated in synchronous island mode until both systems are synchronized. Once the voltage in the DG is synchronized with the utility voltage, the DG is reconnected to the grid and the controller will pass from voltage control mode to current control mode. When the microgrid is working in islanded mode, and the ARL2 detects that the voltage outside the microgrid (in the grid) is stable and fault-free, we have to resynchronize the microgrid to the frequency, amplitude and phase of the grid, in order to reconnect seamlessly the microgrid. If the grid-disconnection cause disappears and the gridvoltage fulfills the desired requirements, the transition from islanded to grid-connected mode can be started. The grid voltage conditions will be again monitored by the Voltage monitoring module. This way if the grid voltage exceeds the threshold value the detection signal is deactivated. If 20 ms after the first detection the detection signal is still deactivated it means that utility grid has returned back to normal operating conditions and the microgrid can reconnect to the grid. However, before the reconnection, the microgrid has to be synchronized with the grid voltage in order to avoid hard transients in the reconnection. To do so, the microgrid operates in synchronous islanded mode during 100 ms with the aim of decoupling the reference variation and the physical grid reconnection transients. In this operating mode the voltage in the microgrid is set to the characteristics of the grid voltage, frequency and phase. Once the voltage in the microgrid is synchronized with the utility voltage the microgrid can be reconnected to the grid and the programmable generator controller will pass from a voltage control mode to a power control mode. In the same way if non-critical loads are detached they are also reconnected. In the presence of unplanned events like faults, microgrid separation from the MV network must occur as fast as possible. However, the switching transient will have great impact on microgrid dynamics. The microgrid functionalities as well as its control methods depend on the mode of operation [23]: Islanding of the MG can take place by unplanned events like faults in the MVnetwork or by planned actions like maintenance requirements. In this case, the local generation profile of theMG can be modified in order to reduce the imbalance between local load and generation and reduce the disconnection transient [48]. Conclusions In this paper the microgrid system installed at the Tallinn University of Technology, has been presented. The microgrid includes a diesel generator, batteries storage with power electronic interface. The architecture of the microgrid for the Tallinn University of Technology and a control system structure for the microgrid were proposed. Design of a control and monitoring system for a microgrid is presented in this paper. A hierarchical control scheme is proposed. This will enhance the reliability and stability of the microgrid on one end and will make microgrid an easy to use product on the other. Acknowledgement This paper was supported by the Project DAR8130 Doctoral School of Energy and Geotechnology II. References A.M.Borbely,J.F.Krieder, Distributed generation: the power paradigm for the new millennium, CRC Press, Boca Raton, Florida, 2001, 388p. P.Nabuurs, SmartGrids, European Technology platform, Strategic Deployment Document for Europes Electricity Networks of the Future, September 2008, 68p. R.Lasseter, Microgrids, Proceedings of 2002 IEEE Power Engineering Society Winter Meeting, vol.1, NewYork, NY, 2002, pp.305-308. B.Kroposki,T.Basso,R.DeBlasio, Microgrid Standards and Technologies, Power and Energy Society General Meeting Conversion and Delivery of Electrical Energy in the 21st Century, 2008, pp.1-4. P.Mazza, The Smart Energy Network: Electricitys Third Great Revolution, Jun. 2003. [online]. Available:, 22p. J.A.Momoh, Smart Grid Design for Efficient and Flexible Power Networks Operation and Control, IEEE Power Energy Society Power Systems Conference and Exposition, Seattle, Washington, 2009, pp.1-8. A.Mehrizini-Sani,R.Iravani, Secondary Control for Microgrids Using Potential Functions: Modeling Issues, Conference on Power Systems (CIGRECanada2009), Toronto, Canada, 2009, pp.1-9. A.Mohamed, Microgrid modeling and online management, PhD thesis, Helsinki University of Technology, Helsinki, Finland, 2008, 169p. D.Yubing,G.Yulei,L.Qingmin,W.Hui, Modelling and Simulation of the Microsources Within a Microgrid, Electrical Machines and Systems (ICEMS 2008), Jinan, China, 2008, pp.2667-2671. C.M.Colson,M.H.Nehrir, A Review of Challenges to Real-Time Power Management of Microgrids, IEEE Power Energy Society General Meeting, Calgary, Canada, 2009, pp.1-8. C.M.Colson,M.H.Nehrir,C.Wang, Ant Colony Optimization for Microgrid Multi-Objective Power Management, IEEE Power Energy Society Power Systems Conference and Exposition, Seattle, Washington, 2009, pp.1-7. S.Ahn,S.Moon, Economic Scheduling of Distributed Generators in a Microgrid Considering Various Constraints, IEEE Power Energy Society General Meeting, Calgary, Canada, 2009, pp.1-6. C.A.Hernandez-Aramburo,T.C.Green,N.Mugniot, Fuel Consumption Minimization of a Microgrid, Industry Applications, IEEE Transactions, 2005, vol.41, no.3, pp.673-681. A.Arulampalam,M.Barnes,A.Engler,A.Goodwin,N.Jenkins, Control of power electronic interfaces in distributed generation Microgrids, International Journal of Electronics, vol.91, no.9, London, GB, 2004, pp.503-524. F.Pilo,G.Pisano,G.G.Soma, Neural Implementation of MicroGrid Central Controllers, IEEE International Conference on Industrial Informatics, New York, 2007, pp.1177-1182. R.H.Lasseter,P.Piagi, Control and Design of Microgrid Components, Final Project Report Power Systems Engineering Research Center (PSERC-06-03), 2006, p. 257. P.Piagi,R.H.Lasseter, Autonomous Control of Microgrids, IEEE Power Engineering Society General Meeting, Montreal, Canada, 2006, pp.1-8. F.Z.Peng,Y.W.Li,L.M.Tolbert, Control and Protection of Power Electronics Interfaced Distributed Generation Systems in a Customer-Driven Microgrid, IEEE Power Energy Society General Meeting (PESGM 2009), Calgary, Canada, 2009, pp.1-8. R.H.Lasseter,P.Piagi, Microgrid: A Conceptual Solution, IEEE 35th Power Electronics Specialists Conference (PESC2004), vol.6, Aachen, Germany, 2004, pp.4285-4290. Y.Che,Z.Yang,K.W.EricCheng, Construction, Operation and Control of a Laboratory-Scale Microgrid, 3rd International Conference Power Electronics Systems and Applications, (PESA2009), 2009, pp.1-5. R.Lasseter,A.Akhil,C.Marnay,J.Stephens,J.Dagle,R.Guttromson,A.S.Meliopoulous,R.Yinger,J.Eto, The CERTS MicroGrid Concept, CEC Consultant Report P500-03-089F. Sacramento, CA: California Energy Commission, 2003, 32p. M.Adamiak,S.Bose,Y.Liu,J.Bahei-Eldin,J.DeBedout, Tieline Controls in Microgrid Applications, Bulk Power System Dynamics and Control VII. Revitalizing Operational Reliability, 2007 REP Symposium, 2007, pp.1-9. H.Gaztanaga,I.Etxeberria-Otadui,S.Bacha,D.Roye, Real-Time Analysis of the Control Structure and Management Functions of a Hybrid Microgrid System, IEEE 32nd Annual Conference Industrial Electronics, (IECON2006), 2006, pp.5137-5142. A.Rà ¶Ãƒ ¶p(editor,reviser), Annual Report 2008 Department of Electrical Drives and Power Electronics, Tallinn: TUT Publishing, Estonia, 2009, 74p. Design and Implementation of a Control System for a Microgrid involving a Fuel Cell Power Module A. P. Agalgaonkar, S. V. Kulkarni, S. A. Khaparde, and S. A. Soman, Placement and Penetration of Distributed Generation under Standard Market Design, International Journal of Emerging Electric Power Systems, Volume 1, Issue 1 2004; Article 1004 TOWARDS A SMART NETWORK IN A BUSINESS DISTRICT. COMBINING DISPERSED UPS WITH DISTRIBUTED GENERATION Designing the Optimal Stand alone Power System which uses Wind Power and Solar Radiation for Remote Area Object Placement and Penetration of Distributed Generation under Standard Market Design Off-Grid Diesel Power Plant Efficiency Optimization and Integration of Renewable Energy Sources Model. Validation and Coordinated Operation of a Photovoltaic Array and a Diesel Power Plant for Distributed Generation Distributed monitoring and control of future power systems via g

Sunday, October 13, 2019

From All the Women Caught in a Flaring Light :: Gay Lesbian

From All the Women Caught in a Flaring Light Imagine a big room of women doing anything,playing cards, having a meeting, the rattle of paper or coffee cups or chairs pushed back,the loud and quiet murmur of their voices, women leaning their heads together. If we leaned in at the door and I said, Those women are mothers, you wouldn’t be surprised, except at me for pointing out the obvious fact. Women are mothers, aren’t they? So obvious. For My Daughter Who Is Not Mine When all the women in my life are mothers, what else can I aspire to be? Aren’t motherhood and womanhood so intricately interwoven so as to run into one another, to become one another? What kind of woman are you if you can’t add to the discussions in the doctor office waiting rooms about nursing this child or that through this malady or that? What kind of woman are you if you can’t re-tell the story of labor and delivery, recounting the hours, the pain, the excess or lack of your child’s hairiness over a church picnic while eating cold fried chicken and coleslaw? What kind of woman are you if you can’t feel the contradiction between the satisfaction of a job well done and the sorrow at a loss for being necessary when your child moves away from home? What else could I be but a mother? So, I am a mother, and yet am also not one, because I can tell these stories about my child with only partial knowledge. I am a non-biological mother of a child with tw o mothers, making my position ambiguous when I share my parenting stories publicly; though, at home, when Aedin calls out â€Å"Momma,† I’m all too happy to be the one she’s calling. The most common question we hear in public is â€Å"who’s the mother?† as people look back and forth between Rachel and me, obviously confused. It’s been asked matter-of-factly by doctors for their charts, shyly by new acquaintances out of curiosity, brazenly by total strangers out of nosiness, and sometimes not even spoken, but implied by a wide range of people knitting their brows in our direction in public places. When I’m out alone with Aedin, no one asks this question; I’m sure Rachel has the same experience. Now that Aedin is verbal, she answers based upon how the person asks it; since I’m her Momma and Rachel is her Mommy, she answers accordingly, but she only looks at them with confusion if they use an ambiguous word such as Mom or Mother.

Saturday, October 12, 2019

Use of Symbolism in Joseph Hellers Catch-22 Essays -- Catch-22

Use of Symbolism in Joseph Heller's Catch-22 The clerk sneezed three times in rapid succession and looked at me through watery eyes. "What did you say your name was?" I told him my name and he turned to a towering file cabinet overflowing with papers and brown manila envelopes. After sneezing three times and searching through a drawer, he pulled out a thin folder and laid it on the counter. "Ah," he said in a nasal voice laden with condescension and impatience. "I see you have no experience in our particular area of expertise. Come back when you get some experience." I explained that I was there to get experience. "Well, I don't see how you can find any work with your experience," the clerk groused, peering at me through a pair of horn-rimmed glasses. "Federal regulation Catch-22." He sneezed three times. I stared, trying to comprehend the logic of this ineffectual bureaucrat. He wouldn't hire me with my level of experience, but I could only get experience by working at this company. He sneezed three times. There was only one c atch, and it was Catch-22. Catch-22 was written in 1961 as a first novel by Joseph Heller, a former army bombardier who got combat experience in World War II from his base on the island of Corsica. Catch-22 became a classic American novel. Heller went on to write several other novels deriding bureaucracy and the military-industrial complex. Catch-22 follows the exploits of an Army bombardier during World War II. John Yossarian and his squadron were based on the small island of Pianosa in the Mediterranean. While the plot jumps all over the place in no chronological order, a story emerges. He loses his nerve for fighting when a man on his plane is killed and Yossarian realizes that the war will be ... ... of Baghdad, and the Sheik of Araby. These amazing facts about Milo seem to imply that he is more than one man. This is supported when Milo gives his syndicate the name M&M Enterprises, implying that it is not a one-man company. These observations led me to put some thought into Milo. I concluded that Milo was meant to symbolize the military-industrial complex that during the 1960s, when the book was written, caught the country in a Catch-22 and held it for decades. The more contracts and power were given to the companies, the more power they had to manipulate the rise and fall of Cold War tensions and continually bloat the military budget. But the companies were needed to combat the threat of Soviet power that hung over the country. There was a catch, and it was Catch-22. Bibliography Heller, Joseph. Catch-22. Dell Publishing Co., Inc, New York. 1961 Edition.

Friday, October 11, 2019

A Life Worth Fighting for

A Life worth Fighting For There are many babies that are born early; many mothers do everything they can to stay pregnant until at least 27 weeks. There are just some things that can't be stopped. There are many families that rely on insurance companies to help out with that cost, but more and more insurance companies are trying to or are turning down premature babies that are born before 27 weeks. Should insurance companies be able to turn down a premature baby because of the risk of being sued? Many hospitals even have doctors that will not help the baby if the insurance will not help out.Many mothers cannot control when they have a baby. There are many hospitals that even tell the mothers that she is fine and that she is just having Braxton Hicks, but in all honestly she is having actual contractions. There are Terbutaline shots that doctors could use to help stop the contractions if they would actually listen to women. There are also different procedures that can be done to stop from someone’s water breaking. There are more and more insurance companies, especially private companies that are trying to turn down babies that are born before 27 weeks.Private insurance companies sometimes have lower deductibles, but there are a lot of things that they are trying to leave out so they do not have to cover. Companies think that preemies before 27 weeks are a liability and if they helped cover the charges and the baby did not make it that the family would go after them and put them out of business. Sadly many companies are finding that either way they can get sued. There are insurance companies that are turning down preemies; making it so the child does not have a fighting chance at life. With insurance companies turning down preemies, the companies should help pay for abortions.The companies are pretty much stating they rather a fetus not have a chance than to try and help pay for a preemie or a child with a down syndrome. There are some states like Oregon a nd Arizona (Abortion Facts) that have abortion laws that are banning abortion, if a state is going to ban abortion than they should make all the insurance companies that are used in that state cover an infant no matter what. Many insurance companies especially private ones are at a higher liability with covering a child born before 27 weeks. There are some many risks that insurance companies could be faced with.For a premature baby to stay in the Neonatal Intensive Care Unit (NICU) for even two days the hospital bill would range from $25,000 to a $100,000. Many insurance companies don't see any type of outcome from that. They think that a family with a low deductable should have to pay more each month for insurance if the family expects them to pay that much for their child. There are also many â€Å"big named† companies that think spending that much on a baby is ridiculous. Yes, to someone that child may be their only child or only chance at having a baby. Insurance companie s look at the long run.Either the deductable is going to go up or the monthly payment is going to go up. Why should we have insurance companies if they are going to have the option of what they cover when the situation arrives? There have been insurance companies that have been sued for babies that do not make it because they were limited the help and the medication the baby was receiving. On the other hand, there are also insurance companies that are getting sued due to turning down a baby and the baby surviving. Many insurance companies if they cover having a baby that early will only support or help pay for certain things.There are a lot of tests like Neonatal respiratory distress syndrome (Premature Infant) that the child needs done and insurance companies refuse to pay for but if the child doesn't have the tests done than the doctors don't know what exactly they need to do to help the baby live. Therefore, there are many babies that do not make it due to an insurance company tu rning down certain things. There have also been many insurance companies that have been sued for turning down helping a family and the child makes it. It is neglect on the insurances part for not giving the chance they deserve.There are quite a few doctors (Smith) (Graham) that refuse to help babies that early because of insurance companies, but there are also doctors that believe a child that early does not have a chance. In 2008 Sara Capewell gave birth to a little boy that the doctors had refused to help or send to the NICU because she was at high risk of having a premature baby and they had told her not to have any more children. (Smith) So the insurance companies are part of the reason infants do not receive proper care, and there are insurance companies get â€Å"lucky† because the doctor refuses to help the family out.There are doctors out there that are only in the profession for the money. They don't care if they are saving a life or not they just want the â€Å"big † paychecks every two weeks. They think that if an insurance company isn't going to help pay for the care of a baby that early than the hospital won't get the money making so they don't get paid. So they turn down families that have no control over the situation. Many mothers are sent home to have the baby so they can have their time with the baby when the infant doesn't make it.How unfair is that to not even give a child a chance because they are worried about not getting paid. Well insurance companies think that they are â€Å"lucky† for there being doctors like that. It makes the hospital look bad not the insurance companies. Every child should have a chance to live. If insurance companies are not going to help a family or mother give that child a chance at life then the insurance company should really look into assisting with birth control and abortion fees. Every child has the right to fight for their life and an insurance company should be there to help no matter what the case is.Works Cited Allen, Vanessa. â€Å"‘Doctors Told Me It Was against the Rules to save My Premature Baby'† Mail Online. 10 Sept. 2009. Web. 22 Mar. 2012. . â€Å"Facts About Abortion: State Abortion Laws (U. S. ). † Abort73. com / Abortion Unfiltered. 10 June 2010. Web. 22 Mar. 2012. . â€Å"Premature Infant: MedlinePlus Medical Encyclopedia. † U. S National Library of Medicine. U. S. National Library of Medicine, 28 Feb. 2012. Web. 22 Mar. 2012. . Smith, Graham. â€Å"England's Healthcare System Allows Premature Babies to Die. † Godlike Productions. 08 Sept. 2009. Web. 22 Mar. 2012. .